Editor's note:Danielle Ofri is associate professor of medicine at New York University School of Medicine and editor-in-chief of the Bellevue Literary Review. Her most recent book, "Medicine in Translation: Journeys with My Patients," is about the care of immigrants and Americans in the U.S. health care system.

(CNN) -- Every time Jade backs into my tiny office, I am impressed. With a skill worthy of a New York taxi driver, she maneuvers her manual wheelchair in reverse into the sliver of space between the exam table and my desk in our crowded city clinic.

Despite her paraplegia from a teenage diving accident, Jade is probably the healthiest 55-year-old in my practice. Recently the topic of handicapped parking permits came up, and I suggested that she would obviously qualify.

I never think of Jade -- not her real name -- as an "illegal immigrant," but technically she is. Twenty years ago, she came to New York as a visitor and then got a religious worker's visa to work at her church. When the church office moved to a second-floor office in a new building without an elevator, she could no longer work. Her visa expired, and she's been in a self-described gray zone ever since.

Confusion about the daunting immigration process, conflicting advice from attorneys, lack of funds to pursue better lawyers and an overall slower and tougher system since 9/11 have contributed to the situation. "You cannot believe how complicated it is," Jade tells me. "I speak English and have an education, yet I found the system impossible to navigate."

Jade knows that she was supposed to leave the country after her visa expired, but she couldn't bring herself to do so. She was helping to raise her niece and nephew after their father died. She was active in her neighborhood church. She felt far more comfortable within the diversity of New York. And by this time, she couldn't deny that America was home.

Immigration issues tend to wax and wane in the public consciousness. During the recent health care debate, the idea that immigrants might derive any benefits from health care reform stoked another round of anti-immigrant sentiment.

Medicine is an interesting vantage point from which to consider immigration. One reason is that despite the inequalities that result in different economic tiers of health care, medicine can still be a great equalizer. Metastatic cancer is metastatic cancer, for example, whether you are a hedge-fund tycoon with roots traced to the Mayflower or an Ecuadorian housecleaner who paid a coyote to get smuggled across the border.

Another reason -- and the one that intrigues me the most -- is that the world of medicine is, itself, a foreign place. When people become ill, they are immigrants from the land of the healthy to the land of disease. This immigration can result in as much upheaval and disorientation as immigration from nation to nation.

As a physician at New York's Bellevue Hospital -- a public hospital in perhaps the most diverse American city -- I have found myself wading in the currents of both types of immigration. The parallels are more than metaphorical, certainly for those who experience both types in their lives.

For Jade, there was the daunting, and of course unrequested, migration from the land of the able to the land of the disabled. Her migration to America and the battle with its Byzantine immigration system is certainly the milder of the two migrations.

As I contemplate Jade's situation, I think about the popular image of "illegal immigrants" and how it rests heavily on the perceived ability of immigrants to hide themselves in society's shadows.

But it isn't as easy to be invisible in a wheelchair. One can't outrun a border guard, or take a less expensive apartment in a walk-up. Most jobs available to those without papers involve physical labor and are unlikely to be wheelchair accessible.

Ordinary day-to-day travel in a wheelchair involves a great deal of visibility. But this seems to suit Jade. Neither disability nor immigration status seem things that need to be hidden. In fact, she's become a Big Apple Greeter -- a volunteer who steps out into the bright light to welcome visitors to New York. She can show them the sights of New York as only a local can, with an insider's knowledge of which subway stops are wheelchair-accessible, which restaurants have wide bathrooms, and where to charge up an electric chair when you are out and about for the day.

"Being in a wheelchair exposes you to the extremes of kindness and of idiocy," Jade tells me. But on the whole, she's found America to be a land of kind and generous people.

In medicine as in immigration issues, individuals are entirely distinct from the population as a whole. Each week, the medical journals report clinical trials, which can tell me many facts about a population, but nothing about my individual patients.

Statistics about immigration also tell me nothing about Jade, whose path to America was entirely unique and whose contribution to American society is one we wouldn't want to lose.

For all its scientific advances, medicine is still a business of individuals. As is immigration. The patients I've met in my clinical practice are individuals who have made many migrations in their lives, from one country to another, from one society to another, from one state of health to another, from one state of mind to another. By considering their lives, by treating their stories with respect and dignity, we can gain insight into the transitions that reflect on all of our lives, since life permits no one to stand still.

The opinions expressed in this commentary are solely those of Danielle Ofri.